As people look to live more healthful lifestyles, many are contemplating meat-free diets. But becoming vegan or vegetarian can seem daunting as people try to figure out what to eat to get all the proper nutrients. Ingrid Beardsley, registered dietitian at MedStar Good Samaritan Hospital, said the transition can be done with proper planning.

What is vegan and how is it different from being a vegetarian?

Vegans exclude all meat, fish, dairy, and eggs, meaning no animal products at all. Some vegans choose to avoid consuming animal products, while others avoid using animal products completely. For example, they may also avoid the use of fur, leather, wool, down, and cosmetics or chemical products tested on animals.

Does age matter when considering the transition to vegan? For instance, is it safe for children to become vegans?

Age should be considered, to ensure that specific nutrients are increased in the diet at specific stages of the life cycle. Protein and essential amino acids should be increased sufficiently in the infant or child's diet. Proteins are built from "building blocks" called amino acids. Essential amino acids must be consumed, because the body can't produce them on their own, like other amino acids. Research indicates that a variety of plant foods can provide all of the essential amino acids required for healthy adults. The major plant food sources of protein are legumes (beans and lentils), cereals, nuts and seeds, and their butters. A combination of these promotes good nutrition at any age.

Studies show that vegetarian and vegan diets can be nutritionally adequate in pregnancy and can lead to positive birth outcome. Strictly vegan pregnant women should ensure adequate intake and supplementation of vitamin B12, D, iron, folic acid, linolenic acid, and calcium. Lactating mothers planning to breast-feed also need adequate calcium, zinc, and DHA, which can be supplemented or received through fortified foods. Infants transitioning to solid foods can meet their needs by replacing strained meat with things like mashed tofu and legumes. At 7 to 10 months, they can try foods such as cubed tofu, soy cheese and pieces of veggie burgers. There is little information about the growth of vegan children, but some studies suggest that vegan children tend to be slightly smaller, but still within the normal ranges of size for age. Frequent meals and snacks, fortified foods (cereals, bread, pasta), and foods higher in unsaturated fats can help vegan children meet their energy and nutrient needs.

Vegan children may have slightly higher protein needs because of differences in protein digestibility (absorption of nutrients into the body), but these protein needs are generally met when diets contain adequate energy and a variety of plant foods. A vegan diet may require intake of calorie-dense foods to provide for adequate growth, and growth should be monitored closely. Calorie-dense foods are foods with more calories in a smaller amount. Including soy products, nuts and nut butters could help to support appropriate growth.

Are there health conditions people should be extra careful about when switching to become a vegan, such as protein deficiencies?

Most health conditions are preventable, with proper planning and monitoring of specific nutrients. Plant protein can meet protein requirements when a variety of plant foods are consumed and energy needs are met. Research indicates that an assortment of plant foods eaten over the course of a day can provide all essential amino acids. Typical protein intake of vegans appears to meet and exceed requirements.

Vitamin B12 deficiency is a potential problem for vegans, so that the use of vitamin B12-fortified foods or supplements are essential. Their diet does not regularly consume reliable sources of vitamin B12, like lacto-ovo-vegetarians who get it from dairy and eggs. Vitamin B12 deficiencies can cause neurological problems. Vitamin B12 deficiencies are stated to be more linked to improper absorption rather than low consumption of vitamin B12.

Vegans tend to have lower blood levels of EPA and DHA (omega 3 fatty acids), which are important for heart, brain and eye health. These can be supplemented or fortified in foods and should be regularly consumed.

Vegans generally have an adequate iron intake and do not experience anemia more frequently than others. However, vegetarians and vegans are recommended to intake 1.8 times more iron daily. This has to do with the "bioavailability" of the iron in meats being a more absorbable form in our bodies.

Vitamin D status is also of concern for vegans, because the supplemental form is not absorbed as well as the animal-derived form. The same absorption factor leads to consideration for risk of zinc deficiencies in vegan diets, but it is also stated that overt zinc deficiency is not evident in Western vegetarians. Lastly, studies suggest that vegans who do not consume key sources of iodine, such as iodized salt or sea vegetables, may be at risk for iodine deficiency, because plant-based diets are generally low in iodine.

What are the benefits of becoming vegan?

In general, vegans tend to have lower blood cholesterol levels, lower risk of heart disease, blood pressure, and Type 2 diabetes. They also tend to have lower risk of cancer and lower BMI (body mass index, a measurement of weight).

Vegans also have higher consumption of whole grains, soy and nuts, which all help protect the heart. Though there is a potential lower risk of cancer, further research is needed to provide more conclusions. An example of a benefit to being vegan is a decreased risk of colorectal cancer. Red meat and processed meat consumption are often associated with an increased risk of colorectal cancer. Vegans do consume considerably more beans, fruits, vegetables, fiber and vitamin C, which also help protect against cancer.

There are also some nutrients that are more highly consumed in vegan diets. These include fiber, magnesium, potassium, vitamin C, E, folate, carotenoids, flavanoids and other phytochemicals. All of which are beneficial to build and maintain a healthy, functioning body.

What are some mistakes people make when they transition to vegan?

Some vegans begin eating the same amount as their pre-vegan days and complain of hunger. They may not be eating enough, because when they move to more whole-plant foods, they now have to eat larger quantities of food, due to the lower caloric density of typical vegan foods.

People also commonly mistake that just because its vegan, it's very healthy. They may load up on processed veggie burgers, cheese, veggie hot dogs and other processed veggie-based foods. Some of these foods aren't providing the nutritional benefits given from whole, nonprocessed foods.

It's also important to not forget to pack snacks when away from the home. Many restaurants now have plenty of options for plant-based eaters, but not all of them. So it's wise to carry snacks (like nuts) if people find themselves in a place where they have nothing substantial to eat. It's also very important to remember to pay attention to the physical needs of one's body. Alterations in diet patterns take time for your body to adjust. Cravings can be a sign that your body needs specific nutrients. Assessing the craving helps to see what is lacking. For example, if a new vegan has been living off salads and is craving fat or salt, they may need to include more healthy fats like avocado or olive oil in their diet. The key is to listen to the body and what it needs.

Nutritionists from the University of Maryland Medical Center help sort through all of the diet and nutrition information that's out there. They provide regular guest posts to the Picture of Health blog.

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